Canadian190e

Need some help diagnosing an issue. I recently bought an 88 190e 2.3 and have had few issues until recently. It should be simple to fix just need some help pinpointing the problem first. Recently, the car has had a dead battery when going to start in the morning a couple times, which I figured was due to an old battery so no big deal. Today after idling for a while, the RPMs started to jump up and down as well as the oil pressure, my radio deck was also continually turning on and off. Seemed like it was having trouble staying running and was not maintaining sufficient and consistent power, and was surging due to no power. Eventually it shut off and was then dead and wouldn't start.

Long story short, im just confused which it would be out of 3 things. Either a bad alternator, battery, or voltage regulator. All seem plausible, but then again it could be something else such as a fuel issue im just not sure, so if someone could help narrow it down that would be great!

*also, when I jump started after it dying, it was doing it again until I would rev it up or drive it

insame1

What trouble shooting have you done?

javelin68

Also check your cap and rotor. Voltage regulator, as you already mention, is also a good suspect..check it to if it's worned out.

Canadian190e

Late reply but replaced the battery as it was very old anyways. Still has the same issues so im suspecting the alternator or voltage regulator for sure. Will check the cap and rotor as well

Canadian190e

Alright, ,little update here. More confused than before. Replaced the battery and had the same problems, so I then replaced the voltage regulator hoping this was the issue as the old one's brushes was shot by the looks of it. Start it up and yet again the same charging problems. Any ways to test an alternator? or am I missing something else that could cause this?

insame1

I'd check all you chassis grounds real quick.

jonathan.144

I had similar issues. Replaced a battery only to find that nothing changed. I did replace the serpentine belt and then the belt tensioner. Pretty simple job, no more issues. Good luck!